Dennis Rodman plans Russia visit to seek release of Brittney Griner

• NBA hall of famer has called himself a basketball ambassador'
• Griner currently serving nine-year sentence in Russia

NBA hall of famer Dennis Rodman says he has permission to travel to Russia as he attempts to secure the release of fellow basketball star Brittney Griner.

Griner was sentenced to nine years in Russian jail for drug possession earlier this month. Her lawyers have filed an appeal and there are understood to be separate talks underway over a possible prisoner swap. But Rodman told NBC this weekend that he plans to make a trip of his own to negotiate the Olympic champion's release.